﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;

namespace Common.Core.Log
{
    public class LocalLogHelper
    {
        static ReaderWriterLockSlim LogWriteLock = new ReaderWriterLockSlim();
        static int WritedCount = 0;
        static int FailedCount = 0;
        static string _contentRoot = string.Empty;

        public LocalLogHelper(string contentPath)
        {
            _contentRoot = contentPath;
        }

        private static void Log(string rootPath, string filename, string[] dataParas, bool IsHeader = true)
        {
            try
            {
                //设置读写锁为写入模式独占资源，其他写入请求需要等待本次写入结束之后才能继续写入
                //注意：长时间持有读线程锁或写线程锁会使其他线程发生饥饿 (starve)。 为了得到最好的性能，需要考虑重新构造应用程序以将写访问的持续时间减少到最小。
                //      从性能方面考虑，请求进入写入模式应该紧跟文件操作之前，在此处进入写入模式仅是为了降低代码复杂度
                //      因进入与退出写入模式应在同一个try finally语句块内，所以在请求进入写入模式之前不能触发异常，否则释放次数大于请求次数将会触发异常
                LogWriteLock.EnterWriteLock();

                var path = Path.Combine(_contentRoot, "Log/" + rootPath);
                if (!Directory.Exists(path))
                {
                    Directory.CreateDirectory(path);
                }
                string logFilePath = Path.Combine(path, $@"{filename}.log");

                var now = DateTime.Now;
                string logContent = String.Join("\r\n", dataParas);
                if (IsHeader)
                {
                    logContent = (
                       "--------------------------------\r\n" +
                       DateTime.Now + "|\r\n" +
                       String.Join("\r\n", dataParas) + "\r\n"
                       );
                }

                File.AppendAllText(logFilePath, logContent);
                WritedCount++;
            }
            catch (Exception e)
            {
                Console.Write(e.Message);
                FailedCount++;
            }
            finally
            {
                //退出写入模式，释放资源占用
                //注意：一次请求对应一次释放
                //      若释放次数大于请求次数将会触发异常[写入锁定未经保持即被释放]
                //      若请求处理完成后未释放将会触发异常[此模式不下允许以递归方式获取写入锁定]
                LogWriteLock.ExitWriteLock();
            }
        }
        /// <summary>
        /// 记录接口请求响应日志
        /// </summary>
        /// <param name="dataParas"></param>
        public static void RequestResponseLog(string[] dataParas)
        {
            Parallel.For(0, 1, e =>
            {
                Log("RequestResponseLog", "RequestResponseLog" + DateTime.Now.ToString("yyyy-MM-dd-HH"), dataParas);
            });
        }
        /// <summary>
        /// 记录接口请求IP日志
        /// </summary>
        /// <param name="dataParas"></param>
        public static void IPLog(string[] dataParas)
        {
            Parallel.For(0, 1, e =>
            {
                Log("RequestIpInfoLog", "RequestIpInfoLog" + DateTime.Now.ToString("yyyy-MM-dd-HH"), dataParas, false);
            });
        }
        /// <summary>
        /// 记录接口请求IP日志
        /// </summary>
        /// <param name="dataParas"></param>
        public static void RecordAccessLog(string[] dataParas)
        {
            Parallel.For(0, 1, e =>
            {
                Log("RecordAccessLogs", "RecordAccessLogs" + DateTime.Now.ToString("yyyy-MM-dd-HH"), dataParas, false);
            });
        }
        public static string ReadLog(string Path, Encoding encode)
        {
            string s = "";
            try
            {
                LogWriteLock.EnterReadLock();

                if (!System.IO.File.Exists(Path))
                {
                    s = null;
                }
                else
                {
                    StreamReader f2 = new StreamReader(Path, encode);
                    s = f2.ReadToEnd();
                    f2.Close();
                    f2.Dispose();
                }
            }
            catch (Exception)
            {
                FailedCount++;
            }
            finally
            {
                LogWriteLock.ExitReadLock();
            }
            return s;
        }

    }
}
